Slot‐die coating is generally regarded as the most effective large‐scale methodology for the fabrication of organic solar cells (OSCs). However, the corresponding device performance significantly lags behind spin‐coated devices. Herein, the active layer morphology, flexible substrate properties, and the processing temperature are optimized synergistically to obtain high power conversion efficiency (PCE) for both the flexible single cells and the modules. As a result, the 1 cm2 flexible devices produce an excellent PCE of 12.16% as compared to 12.37% for the spin‐coated small‐area (0.04 cm2) rigid devices. Likewise, for modules with an area of 25 cm2, an extraordinary PCE of 10.09% is observed. Hence, efficiency losses associated with the upscaling are significantly reduced by the synergistic optimization. Moreover, after 1000 bending cycles at a bending radius of 10 mm, the flexible devices still produce over 99% of their initial PCE, whereas after being stored for over 6000 h in a glove box, the PCE reaches 103% of its initial value, indicating excellent device flexibility as well as superior shelf stability. These results, thus, are a promising confirmation the great potential for upscaling of large‐area OSCs in the near future.

Two allene derivatives, L-and D-N-(1-(octylamino)-1-oxopropan-2-yl)-4-(propa-1,2-dien-1-yloxy)-benzamide (L-1 and D-1), bearing chiral amide pendants were designed and synthesized. Living polymerizations of L-1 and D-1 with allylnickel complex as a catalyst afforded poly-L-1 m and poly-D-1 m with controlled molecular weights and narrow molecular weight distributions. These polymers were found to possess a stable helical conformation with a preferred handedness in aprotic solvents on the basis of their circular dichroism (CD) spectra and specific rotation as well as computer simulation. The helical conformation of the polymers was revealed to be stabilized by elongation of the repeating unit until the degree of the polymerization reaches 80. The slightly influence of temperature on the CD spectra of poly-L-1 100 in CHCl 3 indicated the helical conformation was quite stable at least in the range of 0−55°C. Although poly-L-1 100 showed similar CD spectra in different aprotic solvents, remarkable decrease was observed upon the addition of protic solvents such as methanol due to the weakened hydrogen bonding interactions between the adjacent repeating units. The poly-L-1 100 behaves as a pHresponsive property; the helical structure of the main chain can be transformed to random coil by addition of trifluoroacetic acid to the THF solution which again switches back to helical conformation by neutralization with triethylamine. It was confirmed that the copolymerization of L-1 and D-1 obeyed the majority rule as supported by the nonlinear correlation between the enantiomeric excess of monomer 1 with the CD intensities of the generated copolymers. Atomic force microscope (AFM) and scanning electron microscope (SEM) studies revealed poly-L-1 100 self-assembled into well-defined helical fibrils with distinct handedness. ■ INTRODUCTIONMany biomacromolecules, such as DNA and proteins possess chiral secondary structure, which plays important roles in realizing marvelous biological activities in living systems. 1 In this context, the single-handed helical conformation is often found as one of the most essential higher-order structure. Inspired by the sophisticated biological helices and related unique functions, chemists have been challenged to develop artificial helical polymers and oligomers (foldamer). 2 Synthetic polymers possessing stable helical conformation in solution, like biomacromolecules, are of great interest. Because they can display optical activity sole based on their main-chain helical conformation. The purposes for these researches are not only for mimicking the structure and function of the biological helices but also for their wide applications in materials science. Although some stereoregular macromolecules can take a helical conformation in the solid state, they cannot maintain the helical conformation in solution because of either the inversion of the helix or a change in the structure to random coils. A stable helical conformation requires a backbone that is sufficiently rigid to restrict the rotation. Th...

PHPIT, a new kind of intramolecular donor–acceptor side‐chain‐tethered hexylphenanthrenyl‐imidazole polythiophene is synthesized. The more‐balanced electron and hole mobilities and the enhanced visible‐ and internal‐light absorptions in the devices consisting of annealed PHPIT/PCBM blends both contribute to a much higher short‐circuit current density, which in turn led to a power conversion efficiency as high as 4.1%.

Facile synthesis of hybrid block copolymers containing two segments that cannot be synthesized under the same polymerization mechanism still remains a great challenge in the field of polymer synthesis. Here we report on one-pot synthesis of hybrid block copolymers containing conjugated poly(phenyleneethylene) (PPE) and stereoregular poly-(phenyl isocyanide) (PPI) using palladium(II) complex as a single catalyst. Although the two blocks were polymerized via distinct polymerization mechanism, the block copolymerization were revealed to proceed in a living/controlled chaingrowth manner, afforded PPE-b-PPI block copolymers in high yields with controlled molecular weights, narrow molecular weight distributions, and tunable compositions. By using this synthetic method, amphiphilic PPE-b-PPI block copolymers containing hydrophobic PPE and hydrophilic PPI segments were facilely prepared. Such block copolymer can self-assembly into welldefined supramolecular structure in selective solvents. In addition, the one-pot block copolymerization method can be applied to the preparation of other hybrid block copolymers such as PPE-b-poly(1-isocyanohexadecane) (PPE-b-PIH) and PPE-bpoly(quinoxaline-2,3-diyl) (PPE-b-PQD) under living/controlled chain-growth manners.

Conjugated block copolymers with tunable properties have attract considerable research interests in recent years. Herein, we report a series of novel block copolymers containing conjugated poly(3-hexylthiophene) (P3HT) and poly(triethyl glycol allene) (PTA) segments which were synthesized in one pot using nickel complex as a single catalyst via distinct polymerization mechanisms. Interestingly, the P3HT-b-PTA diblock copolymers exhibit excellent thermoresponsive properties in water, and the lower critical solution temperature (LCST) is dependent on polymer concentration and the block ratio. Moreover, the diblock copolymers showed pH-responsive properties in CHCl 3 with the emission color shuttled between orange and deep green upon the alternate additions of trifluoroacetic acid and triethylamine. Both P3HT-b-PTA and P3HT-b-PTA-b-P3HT block copolymers exhibit solvatochromism properties. The emission of the block copolymers can be facilely tuned through variation on solvents with the emission color spanned widely from red to blue. Very interestingly, white-light emission can be readily achieved from the P3HT-b-PTA-b-P3HT triblock copolymer in the mixture of THF and methanol with 1/3 volume ratio.